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Python Sets vs Lists
...move the object creation now. The setup phase of the timeit loops is only called once (docs.python.org/2/library/timeit.html#timeit.Timer.timeit).
– Ellis Percival
Sep 30 '14 at 10:09
...
What is the size of an enum in C?
...set of enum values, but I need each enum value to be 64 bits wide. If I recall correctly, an enum is generally the same size as an int; but I thought I read somewhere that (at least in GCC) the compiler can make the enum any width they need to be to hold their values. So, is it possible to have an e...
How can I dynamically create derived classes from a base class
...
This bit of code allows you to create new classes with dynamic
names and parameter names.
The parameter verification in __init__ just does not allow
unknown parameters, if you need other verifications, like
type, or that they are mandatory...
Getting a map() to return a list in Python 3.x
...ases, this ends up saving memory, and should make things go faster.
If all you're going to do is iterate over this list eventually, there's no need to even convert it to a list, because you can still iterate over the map object like so:
# Prints "ABCD"
for ch in map(chr,[65,66,67,68]):
prin...
ObservableCollection not noticing when Item in it changes (even with INotifyPropertyChanged)
...
The ContentList's Set method will not get called when you change a value inside the collection, instead you should be looking out for the CollectionChanged event firing.
public class CollectionViewModel : ViewModelBase
{
public ObservableCollection<E...
res.sendFile absolute path
...pond with index.html on every request, because I'm using a star * to catch all files that weren't found in your static (public) directory; which is the most common use case for web-apps. Change to / to return the index only in the root path.
...
Multiple file upload in php
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I'm not sure <input type="file"> allows the attribute multiple - what would the expected outcome be? Browser allowing multiple files to be selected?
– Sven
Oct 3 '12 at 17:41
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Can I access constants in settings.py from templates in Django?
...neric views, and many of the core and contrib apps, additional context is called extra_context, and very often it is included in the view's arguments.
– Soviut
Jun 1 '09 at 1:33
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How can I force division to be floating point? Division keeps rounding down to 0?
... a floating point number in Python in the following?
c = a / b
What is really being asked here is:
"How do I force true division such that a / b will return a fraction?"
Upgrade to Python 3
In Python 3, to get true division, you simply do a / b.
>>> 1/2
0.5
Floor division, the classic di...
Boost.Asio的简单使用(Timer,Thread,Io_service类) - C/C++ - 清泛网 - 专注C/C++及内核技术
... asio::write(socket, asio::buffer(message),
asio::transfer_all(), asio::ignore_error());
}
}
最后处理异常
catch (std::exception& e)
{
std::cerr << e.what() << std::endl;
}
return 0;
运行示例:运行服务器,然后运行上一节的客户端,在win...